Fracture response of cement-based composite with spherical glass aggregate exposed to high temperatures

11th International Scientific Conference of Civil and Environmental Engineering for PhD. Students and Young Scientists

土木建筑工程;生态环境科学

Rozsypalová, I.^1 ; Kumpová, I.^1^2 ; Majda, T.^1 ; Kerner, Z.^1 ; Štancl, P.^3

Brno University of Technology, Faculty of Civil Engineering, Vevei 331/95, Brno

602 00, Czech Republic^1

Czech Academy of Sciences, Institute of Theoretical and Applied Mechanics, Centre Tel, Batelovská 485, Tel

588 56, Czech Republic^2

Statika 3 Structure S.r.o., Designing Company, Ná m. SA 39, Moravské Budjovice

676 02, Czech Republic^3

关键词: Cement based composites;    Degree of damages;    Effective fracture toughness;    Monitored parameters;    Reference specimens;    Temperature loadings;    Three-point bending test;    X-ray micro tomographies;   

Others  :  https://iopscience.iop.org/article/10.1088/1757-899X/566/1/012027/pdf
DOI  :  10.1088/1757-899X/566/1/012027

来源: IOP

【 摘 要 】

This paper concerns an investigation into the effects of high temperatures acting on specimens made from specially designed fine-grained cement-based composite with spherical glass aggregate. The experimental programme was carried out on four sets of beam specimens with the dimensions 20 × 40 × 200 mm. The specimens were thermally loaded to pre-set temperatures of 100, 200 and 400 °C, after which these temperatures were maintained for 60 minutes (one of the sets contained three reference specimens which were placed in a laboratory at a temperature of 20 °C and were not exposed to heat). After the temperature loading had been performed, the specimens were left to cool down to ambient temperature. After that, fracture tests were used to determine the degree of damage caused to the specimens by temperature loading. Three-point bending tests were conducted on the previously loaded beam specimens, which were notched to provide them with an initial stress concentrator using a diamond blade saw before testing. The depth of the initial edge notch on the bottom side of the specimen was approximately 1/3 of the total specimen depth. The span length was 180 mm. Fracture response was evaluated via load versus deflection diagrams. The monitored parameters were modulus of elasticity, effective fracture toughness and specific fracture energy. Informative compressive strength values were also determined. Selected specimens were investigated using X-ray micro-tomography (micro-CT).